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Mirror-less

Swissblad said:
As far as I can see it is not the number of pixels that count, but pixel size and the fact that MF is 16 bit.
Click to expand...

The SLR mirror concept was developed as a way to preview the image in an analog camera using film. Unfortunately the mirror introduces a number of problems including body size, limited responsiveness, mirror dynamics, vibrations and noise. The mirror concept also relies on creating a secondary and simulated optical path for focus and exposure measurements. The accuracy of this secondary optical path is sensitive to camera accuracies and tolerances and it shifts with temperature and mechanism wear. The SLR mirror also prohibits natural compensation for image plane variations between different lenses.

The digital image sensor eliminates the need for these compromises.
What is missing today is an EVF of the same quality as the image sensor.
Once you have experienced a high resolution digital camera with a high resolution EVF your paradigm will shift.

The advantages of the fully digital, mirror-less camera aside from eliminating the compromises mentioned above include exact focus, pinpoint focus by zooming and panning the EVF independent of the lens framing, exposure preview, white balance preview, lens effects preview etc. In other words, you can now inspect your image before you take it rather than after.

As to your overly simplified statement above, each photographic application probably has an optimum resolution past which there is little or no economic or visible return. However, since we are talking about top quality images there is no question that optimum lens sharpness, pinpoint focus, optimum image sensor resolution and noise free pixel reproduction are key requirements.

The SLR mirror does nothing but compromise several of these requirements.
 
I have no doubt that mirror-less systems can be effective - but - as I pointed out - non exist professionaly in the current dSLR or other markets.

It seems illogical for a small company like HB to enter this arena - when even Canikon are steering clear at the moment.

While I'm not sold on mirrors - I just like to have a pretty good approximation of what the image may look like - and currently mirrors still offer a better approximation than current EVFs..... the future may well be different.

That said - my next move may be to an ALPA...
 
Bengt - I agree with the points you raised about mirrors - but I feel we're a long way off from effective EVF's.

That said, it doesn't change my opinion about a CaNikon with 40 mp.... since

the "old" Leaf Aptus with 22 MP still puts many dSLRs to shame.
 
Swissblad said:
... the future may well be different.
Click to expand...
The majority of new cameras coming out in 2012 will be mirror-less. Several will be SLTs with excellent EVFs.
I agree that it will be a few years before EVFs reach the top of the line, that's why HB and others need to start preparing for it today.
 
I'm sure the Hasselblad engineers are aware and thinking about advancements in EVF and various other innovations in digital photography. So, I wonder why worry about it?

While some cameras are moving in this direction, it is a good point made by someone earlier that the higher spec ones aren't yet. Canon's latest, greatest full frame 1DX has many new innovations, but not in the area of mirrorless.

I think we have to remember that a majority of these MFD cameras are used by professional photographers or very advanced enthusiasts. Many of the benefits of a mirrorless system don't exactly fit into their methodology or applications.

For example, a lot of landscape photographers don't even use the SLR camera body ... they mount the back on a technical camera using leaf shutter view lenses. Another fairly common application for these cameras is shooting tethered to a computer ... ether in the studio to a tower, or to a lap-top in the field ... both of which provide a large screen sized image for client review.

I've shot with a couple of different mirrorless cameras, and the technology is very promising for certain types of applications ... but for the life of me I can't see the benefits as applied to MFD and how they are used in the real world.

-Marc
 
fotografz said:
... the technology is very promising ... but for the life of me I can't see the benefits as applied to MFD ...
Marc
Click to expand...
I agree that a tethered computer viewing screen many times is the preferred solution. However, sometimes it's nice to be able to leave all that equipment in the studio.

An integrated EVF then offers the same advantages to MFD as it does to other formats.
 
Clients can't see the EVF or be able to tell much from a 3" live view LCD ... which is why, even on location a laptop is used ... and now even wirelessly on an iPad.

Can't use mirrorless or EVF on a tech camera ... maybe someday, but the tech camera makers don't seem all that interested.

What you want is something that has low application and high cost for a majority of MFD users. This equipment is already very expensive.

A MUCH more useful application of technology and R&D resources for Hasselblad to look at would be a focal Plane shutter H camera body that would allow shutter speeds to 1/4000th, and with a flip of a switch utilize the 1/800th sync speed of the Leaf shutter HC/HCD lenses.

When Leica finally gets the CS lenses to market, that is exactly how it'll work ... 1/4000th, and flip the switch from FS to CS and use the leaf shutters in the lenses for sync up to 1/500th instead of 1/125th.

IMHO, innovation should meet real world needs, not low demand technology for the sake of technology.

-Marc
 
Understood.

I'll leave "tomorrow" to the Hasselblad Engineers and market forces, neither of which I have any control over.

It will be interesting to see which MFD company goes to a CMOS sensor first. I was surprised that the two newest players didn't try it ... Pentax and Leica, especially Pentax which most appeals to 35mm DSLR users who are used to CMOS IQ and look. It would have made it an even more alternative choice for those looking to move up to MFD.

There must be a reason, and I suspect it is Image Quality, or the fear that it won't match the current quality in the eyes of very critical MFD users, whether it actually does or not.

Maybe no sensor company even makes a CMOS sensor that big. ????

Marc
 
Using CCD technology versus CMOS technology for the image sensor has nothing to do with your choice of image viewer. There is no reason to think that to use an Electronic View Finder you must use a CMOS image sensor.

CCD vs. CMOS

CCD (charge coupled device) and CMOS (complementary metal oxide semiconductor) image sensors are two different technologies for capturing images digitally. Each has unique strengths and weaknesses giving advantages in different applications. Neither is categorically superior to the other, although vendors selling only one technology have usually claimed otherwise. In the last five years much has changed with both technologies, and many projections regarding the demise or ascendence of either have been proved false. The current situation and outlook for both technologies is vibrant, but a new framework exists for considering the relative strengths and opportunities of CCD and CMOS imagers.
Both types of imagers convert light into electric charge and process it into electronic signals. In a CCD sensor, every pixel's charge is transferred through a very limited number of output nodes (often just one) to be converted to voltage, buffered, and sent off-chip as an analog signal. All of the pixel can be devoted to light capture, and the output's uniformity (a key factor in image quality) is high. In a CMOS sensor, each pixel has its own charge-to-voltage conversion, and the sensor often also includes amplifiers, noise-correction, and digitization circuits, so that the chip outputs digital bits. These other functions increase the design complexity and reduce the area available for light capture. With each pixel doing its own conversion, uniformity is lower. But the chip can be built to require less off-chip circuitry for basic operation.
 
Understood.

As far as I understand it, live view is not a possibility with CCDs but is common with CMOS cameras. Live view is the missing element in effective use of a MFD camera for some limited applications. Phase One has innovated a way of providing LV with a CCD in a very limited manner compared to a 35mm DSLR

I also wonder if the CCDs avalanche type transfer can refresh fast enough for EVF/Live view ... when you tether a MFD back and use the live view feature, the response is extremely slow.

I suppose the EVF could be separate from the sensor ... isn't that the way the Sony EVF SLR cameras work using a translucent mirror? Their next version of EFV is now available in the A77 ... but it is still a long way off to replacing an analog finder. I've used a Sony EVF camera, and absolutely hated it.

-Marc
 
Isn't it the size of the sensor that is the issue? Consumer video camera sensors and P&S cameras are tiny, so video feed from the sensor to the EVF should be okay even with the slower CCD feed ... note that the RED video cameras with larger capture area use CMOS sensors.

How well could a 645 sized CCD at 60 meg refresh the RVF? And how much power drain would that present?

I think at this stage, EVFs are consumer level think trying to be applied to professional level need.

As mentioned in a recent Mac World article comparing EVF and OVF ... "... a streaming video feed may never be clear or responsive enough, or accurately show enough dynamic Range for some photographers."

I'm one of those photographers, at least where the technology stands today. I'll leave tomorrow to the engineers to monitor and adopt new technologies as they become viable, and then I'll make up my mind.

EVF/SLTs are currently all CMOS sensor cameras and even then the refresh rate is limited by the time it takes the sensor to form an image ... so there is a stagger effect when panning with a subject.

I also found the SLT cameras really irritating due to the slow recovery time after the shot. There is no real time update at higher shooting rates because the viewfinder shows the last shot taken, not where the lens is pointed. I can't imaging what that would be like with a huge MFD CCD sensor feeding the EVF.

Not ready for prime time.

-Marc
 
Bengt - pardon this blunt question - but - do you use DMF cameras at all - either professionally or serious amateur.... or just stirring the pot?
 
I think it is a legitimate question whether one uses a MFD or not.

However, part of the question has to include real world needs of those who DO use MFD either for a living, or as a serious personal pursuit.

I most certainly am not anti-technology and use the latest features of the H4D camera to good result. I am however, not all that interested in technology for the sake of technology. It has to translate into a substantial improvement in how I work with these cameras. It cannot just be an alternative technology that improves one thing at the expense of another ... which my experience with EFV has been to date.

-Marc
 
fotografz said:
I think it is a legitimate question whether one uses a MFD or not.

However, part of the question has to include real world needs of those who DO use MFD either for a living, or as a serious personal pursuit.

I most certainly am not anti-technology and use the latest features of the H4D camera to good result. I am however, not all that interested in technology for the sake of technology. It has to translate into a substantial improvement in how I work with these cameras. It cannot just be an alternative technology that improves one thing at the expense of another ... which my experience with EFV has been to date.

-Marc
Click to expand...

Thanks for putting that so eloquently Marc.... my comment was a bit slapdash.
 
To help the push in the right direction, let me say that unless I have a living subject I alway close the mirror before shooting - ever since the 1000F. I do appreciate the (new) user programmable button that allows me to delay the shutter until the mirror vibrations have ceased. The mirror is a leftover from ancient times.
 
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